The present invention relates to an improved wavelength meter suitable for use in an atomic vapor laser isotope separation (AVLIS) process.
Wavelength meters are known in the prior art for determining the wavelength of light sources, such as monochromatic radiation from a laser source. One well known prior art approach is described in U.S. Pat. No. 4,173,442 issued Nov. 6, 1979 to James J. Snyder for "Apparatus and Method for Determination of Wavelength." In the '442 patent, there is disclosed therein an improved wavelength meter which includes a data processing capability for determining the wavelength of a laser beam.
While that processing capability is suitable for some applications, in general that degree of accuracy may not be suitable for use in an AVLIS process. In an AVLIS process, organic dye lasers are utilized to photoionize an atomic vapor, such as uranium vapor. In such a process, it is necessary to determine the accuracy of the photoionizing laser beams(s) with a very high degree of accuracy, say two parts in 10.sup.8. The accuracy requirement is the subject of a cross-referenced application entitled "Improved Wavelength Meter Having Elliptical Wedge," Ser. No. 915,200, filed Sep. 25, 1986 the details of which are hereby incorporated by reference.
Another aspect of the AVLIS process is that a plurality of laser sources are required because of the different photoionization levels for the different types of atomic vapor (typically uranium) isotopes. In such an environment, the wavelength of each of the laser sources must be determined with a high degree of accuracy. It would be highly desirable to provide an architecture that could determine wavelength, with the required accuracy, any one of a plurality of laser sources for use in an AVLIS application.